Snowden told Greenwald: “I have never spoken with, worked with, or provided any journalistic materials to the Independent.

"It appears that the UK Government is now seeking to create an appearance that the Guardian and Washington Post's disclosures are harmful, and they are doing so by intentionally leaking harmful information to The Independent and attributing it to others. The UK Government should explain the reasoning behind this decision to disclose information that, were it released by a private citizen, they would argue is a criminal act."

He said that a tactic used by the US Government is “aggressively targeting those who disclose embarrassing or incriminating information about the government in the name of protecting the sanctity of classified information, while simultaneously leaking classified information prolifically when doing so advances their political interests".

He also said he had made no agreement with the UK Government over coverage.

He said: “I'm not aware of, nor subject to, any agreement that imposes any limitations of any kind on the reporting that I am doing on these documents.”

The Independent's Wright has emphatically denied the suggestions made by Greenwald.

He said on Twitter: "For the record: The Independent was not leaked or 'duped' into publishing today's front page story by the Government."

He also said that Greenwald had not contacted The Independent in advance of publishing his blog post and rejected the suggestion that his paper should reveal the sources for its story.